I'm in the midst of my 3rd vintage build using modern components. A couple of gotchas you may run into... Not insurmountable but a pita:

-Headset cup diameter. Hopefully your frame requires 30.2mm as these are plentiful. Some frames are 30.0mm and these are more scarce.

-Brake bolt diameter and length. Sometimes they bolt right up, other times you have to get creative with the parts bin.

-Front brake clearance with headset bottom cup. Just encountered this with a new 105 5800 brake caliper. It's bulky on top and hits the cup. Required some spacers from abovementioned parts bin.

-Front derailleur clamp diameter. Make sure it fits your tube diameter. If not, there are shims available for this.

Good luck with the project!